Concrete coating machine



June 5 1959 E. ROBERTSON ET AL 2,890,837

CONCRETE COATING MACHINE I Fild March 7, 1956 5 Sheets-Sheet 1 INVENTOR.

June 16, 5 E. ROBERTSON ETAL 2,390,837

7 CONCRETE COATING MACHINE Filed March '7, 1956 3 Sheets-Sheet 2 IN VEN TOR (Emma/am June 16, 1959 E. ROBERTSON ET AL 2,890,337

CONCRETE COATING MACHINE Filed March 7, 1956 3 Sheets-Sheet 5 IN VEN TOR.

Ema/1w BY @acax CONCRETE COATIN G MACHINE Evans Robertson and Oscar Langhans, Lombard, 111., as-

signors to Pipe Line Service Corporation, Franklin Park, 11]., a corporation of New Jersey Application March 7, 1956, Serial No. 570,150

17 Claims. (Cl. 239-21S) This invention relates to apparatus for applying coatings of plastic material and particularly to apparatus for applying concrete coatings to pipe. templates improvements in concrete coating machinery of the type wherein concrete, in plastic or fluid form, is conveyed by means of a worm conveyor to a pair of rotating brushes which, in turn, impel the concrete onto the surface of a rotating length of pipe which is moving parallel to the axis of rotation of the brushes.

Machines of this type generally utilize conveyor worms having one or two points, the points referring to the leading edges of the worm flights. All of the worms previously used tended to give a rough finish on the coated pipe excepting when the worms were new. Single flight worms are not practical due to the uneven thickness of coating which results from their use.

.One of the objects of this invention is to provide a three point worm, all of the flights being of constant diameter which, compared to worms having .tapered flights, are inexpensive to fabricate andwhich will give a smooth finished pipe coating along with higher production rates than can be obtained with worms presently in use. 1

Another object of the invention is to provide a pipe coating machine which can be easily disassembled for either cleaning or repairing.

It is also an object of this invention to provide a pipe coating machine wherein the rotating impeller brushes have increased efliciency of operation due to alleviation of clogging tendencies. v i

Other objects and advantages will be apparent from the following specification and from the accompanying drawings in which:

Figure. l is a side elevational and in which certain portions of the machine have been broken away for clarity;

Figure 2 is a vertical section taken at line 2-2 of I Figure l Figure 3 is an enlarged section taken at line 3--3 of. i

Figure 1 showing theclean-out door structure;

The invention coni 15. The trough or material conduit portion, which is shown in Figures 1 and 2 comprises a trough body 16 having preferably downwardly converging side walls 18 merging with an integral bottom wall 20 which is radiused laterally of the trough as shown in Figure 2. Flanges 22 extend horizontally outward from each side ot the trough to receive a conventional hopper 24, which may be bolted or otherwise secured to the flanges. The trough is provided with a front end plate 26 and a rear end plate 28, which extend below the trough bottom 20, and are secured to the frame 15 in any conventional manner as for example by angles 23 welded to the plates and bolted to the frame. The bottom portion of the trough. is provided 3) is provided in the upper portion of the cylindrical body 30, and the portion of the cylinder which was cut away to provide the opening, or a piece similar thereto, is utilized as a removable clean-out door 36. A plurality of V radially disposed lugs 38 are welded to the cylindrical body 30 adjacent corresponding lugs 40, which are welded to the door 36. The cover is held in place by means of bolt and nut assemblies 42 passing through adjacent pairs of lugs. v

The end of the nozzle is indicated generally at 44, and comprises a sleeve 46 (Figure 4) split as at 47 and adapted to surround the cylindrical body 30. The sleeve may be clamped in the desired position by means of a bolt and nut assembly 50:, passing through adjacent lugs 48 which are welded to the sleeve. Secured to the sleeve 46 is a vertically disposed backing plate 52 which is sup.- ported by gussets 54 extending between the hacking plate and the sleeve. The cylindrical body 30 extends through and outwardly of the backing plate 52 and is cut away above andbelow the center line of the body 30 'as at 53-53 to provide a mating contour for the impeller brushes to prevent thereby loss of material laterally of the brushes. The brushes are indicated schematically at 72. The nose portion 56 of the sleeve 46 also extends through and outwardly of the backing plate 52 and is cut away as at 5858. The contours 58-58 are different from the contours 53--53, and therefore the contours 58-58 meet at a point further removed from the center "line of the brushes than the meeting point of the contours Figure 4 is an end elevational view taken at line 4-4 Figure 7 is a top plan view of an alternate embodiment of the discharge nozzle; and

Figure 8 is a longitudinal vertical section taken at the line 8-8 of Figure 7.

Referring to the drawings and particularly; to Figure 1, y

it is seen that the machine comprises a nozzle portion,

a side elevational view of the p referred type 53--53. The reason for this is that asthe brushes decrease in diameter due to wear, the sleeve 46 may be moved outwardly toward the brushes whereupon the contours 58-58 of the nose portion 56 will extend beyond the end contour 53-53 of the cylindrical body 30 to i once again adequately prevent loss of material. The

projecting end of the body 30 and the nose 56 of the f sleeve 46 are each provided with a horizontally disposed slot 60 adapted to receive a splitter plate 62, the purpose of which is to prevent spiralling of the plastic or fluid secured thereto in any desired manner, but preferably by generally indicated at 10, adapted to receive plastic mate 5 rial from the trough portion, generally indicated at 12,

and includes a drive portion, indicated generally at 14. The entire machine is .preferablymounted on a frame concrete as it emerges from the nozzle. The splitter plate is provided with a rod 64 adjacent one side of the plate, the rod being received in a tube 66, which is welded to a plate 68 extending longitudinally of the sleeve 46. and

welding. A set screw assembly indicated generally at 70 is provided to lock the alignment rod 64, and thereby the splitter plate 62, in the desired position. The split sleeve 46 is preferably :detachably mounted onthe nozzle, and @this is illustrated as being accomplished by means ofone Patented June 16, 1959 or more threaded nuts 74 welded to the sleeve, and cap screws 76 extending through the nut and sleeve and bearing against the outer surface of the cylindrical body 30. In, the past it has been thought necessary to provide splash uards fo h bru he which sta t lly ene es the p, bot om n v ides of h b ushe he c ief hi ieulty ith h s ty e f str ctur b sides i h gh is. the a t that the fl con r e ds to pile up in the space tween the plash guard and the eu ersu aee of the rushes, and t rough this clogging tendeney g ea ly re. 1 h impellingefficiency of the rushe Accor ing to p e e t nvention material loss is adequate y pie-'- e i d. y means of a su stantia y fiat bac ing plate 52,

po i i ned. mm diately at t e a o th brushe to -M et er. w t the con r d n e pie e of t e body 1. 0 an lee er lfi and furthermore w th this type of p ash ua d; Pra t a y a l of th t nd n y .of the brush t beeeme clogged with fluid concrete is eliminated.

Referring again to Figure 1, flange 31 and plate 26 are provided with aligned openings 78 adapted to receive a conveyor wonn, indicated generally at 80,.extendingfrom a point adjacent end plate 28, through the trough and nozzle, substantially to the back ng Plate 52. The worm 80 comprises a central shaft 82 and three helical worm flights 84, 86 and 88 (Figures 5 and 6.). The .worm flight 84 is of a constant diameterand extends substan. tially for the :entire length of the shaft 82 which will requi e at least one convolution of the flight and usually several convolutions. This flight also preferably a constant pitch. Worm flights 86and88 have their leading edges, or points, in the same radial plane as-the leading edge of flight84, but the leading edges of vthe three flights are preferably angularlyspaced at 120", as shown iniFigure ,6. ,In the preferred form of the invention, the flights 86 and 88 extend along the shaft 82 for approximately 0,f a convolution, or, inother words, about 180 of revolution about the shaft. The length of the two partial flights may, of course, be varied to some extent but .it has been found that the best results areobtained when they are of a length asdescribed in the preferred form. The above type of worm structure has several advantages .over those employed in the past on machines ofthis type. They are much lesscostly tofabricatethan Worms having a varying pitch, or a varyingdiameter. They are also less subject to wear and are more eflicient in operation, and apply an extremely S IQOthc ating of uniformthickness such as wasnot readily obtainable with other types of worms.

The end of the worm adjacent the plate 28 is provided with ,a flange 90. The flange 90 is secured to a correassess-7 conveyor worm,

Figures 7 and 8 illustrate an alternate form of discharg nozzle for thefluid. concrete. Referring .to these figures, it is seen that the cylindrical body 30 is similar to that described hereinbefore, and is similarly provided with a -gu ee 34. h xtreme -9 1i end o t e ey spending-flange 92 on the end of drive shaft 94. The

flanges 9 0.and 92 may be detachably connected inany desired manner, but preferably would be positioned by meansof dowel pins 98, and secured to eachother by meansofaplurality of cap screws 96. Thistflanged connection together with the constant Ldiameter conveyor wormflights areimportant featuresof thepresent-inventioninthat they permit the worm to be removed, when necessary,..through:the front end of them ehine without the necessity of rdisassemblingsor disturbing any,portion of the drive assembly 14. In previous machines where aitaperedwworm andasinglecontinuous shaft wereiused,

it was necessary to completely disassemble. the entire drive assembly. and remove the Worm through therear-ofihe machine whenever such removal was necessary- 51s ,for

replacementor repairs. Thisjob required up to fiveor six-hours laborfor three porr fourmen. ,Using'the teaehingsofthe; present invention, whereina constant diameter worm ,and .a flanged connection between the worm shaft and the drive shaft is used, the ,worm may.b e removed e t e ro b one a i en ieisima e fifteen minutes.

Thetdrive for the conveyor worm comprises :a drive ha t 9.4 ;re .-a .a ly mounted in combine radial :thni t bearings 100,1-Whi9h are carried by vertically :projecting 275 plat 2 ha in their front e ges r s t6 ma li' heopening 111.are welded to the tube 30. The outer edges 113 of 'the face plates 112 provide abutment surfaces against which are placed guard plates 11,4, Preferably the guard plates are provided with a plurality of open? ings 115 by means .of which plates 11,4 maybe Welded he c lin r ca bed 0' The pl tes 11 are d tien' l y provided with locking straps 116, which project inwardly of ,the plates and extend parallel to, but spaced from, the face plates 112. Insertable between the plates 112 and straps 116 are upper and lower adjustment plates 118 By sliding these plates ,angularly toward and away from the center line ,of the discharge nozzle, the amount @of opening available for the discharge of the fluid concrete may be varied as desired. Cross bars 120, secured to and extending transversely of the plates 118 may be provided for thedual purpose of strengthening the plate and of providing a convenient means for moving the plate toward either open or closed position. The plates 118' va e held in the desired position means of acap screw 124 received within a'nut 122 which is welded to. the

outer surface of the plate 118. The screw 124 Passes.

118 and straps 116 to take up the excess clearance.

The above typeof nozzle has several advantages. As

seen in Figure 8, the lower adjustment plate may be ex tended to. a point overlapping the brush 72. iI'herecan therefore be no spillage of the fluid concrete as it is being transferred from the nozzle to the brushes. Also type of structure is less complicated and .less expensive to fabricate than other types now in use; Furthermore, the nozzle may be easily cleaned merely by looseninglrth'e cap. screws 124 and sliding the plates 118 outwardly t o give access to .the inside of .the tube through the openings formed at surfaces 111. Another advantage isith at this type of structure provides an easily adjustable orifice by means of which the proper flow of concrete 'mixma be readily attained. Still another advantage .is that the necessary pressure on the concretemixture is obtained h u h re t eh e bt inn sid efih late 11 rather .thanby reaction against the brushes thereby increasing the life of the brushes and contributing greatly toward uniform wear of the brushes rather than coneshaped hich seurs er tir of was We claim:

ou e on s id frame; a h pp .eemmuniset g-iriih s i eqnduica d ve shaft e atab y .uieu te n s d "frame, one endtgfsaid ,shaftbeing received conduit; power [means ztQ drive .said shaft; a .wormdisd posed lengthwise in said conduit for advancing coating material therethrough; a separable flanged connection between said shaft and said worm whereby said worm may be removed through the discharge end of said conduit without the necessity of removing said shaft, said worm comprising a single helical flight extending substantially the full length of the worm, and two additional flights at the discharge end of said worm, each of said additional flights having a helical travel of approximately 180"; a pair of cylindrical brushes adjacent the discharge end of said conduit; and a substantially flat backing plate interposed between said brushes and the discharge end of said worm.

2. In a machine for applying plastic coatings, the combination of a frame; a horizontally disposed conduit supported by said frame; a drive shaft rotatably mounted on said frame and extending into the feed end of said conduit; a three point worm disposed within said conduit for advancing material therethrough; a removable flanged connection between said shaft and said worm; a pair of cylindrical brushes at the discharge end of said conduit for receiving material from said worm; and a substantially flat backing plate disposed between said brushes and said worm.

3. A device for applying plastic coating material; said device comprising a material carrying conduit, a pair of rotatable brushes at the discharge end of said conduit for receiving material therefrom, a worm disposed within said conduit for advancing material therethrough toward said brushes, said worm comprising a helical flight extending substantially the full length of said worm and a pair of partial flights at the discharge end of said worm, all of said flights having their leading edges in substantially the same radial plane, said partial flights extending through a spiral travel of approximately 180.

4. A device according to claim 3 and including a drive shaft assembly, and a separable flanged connection between said worm and the drive shaft.

5. In a device for applying plastic coating material, the combination of: a frame; a bearing carried thereby; a material carrying conduit mounted on the frame; said conduit having a discharge end; a power driven worm shaft rotatably mounted in said bearing and extending into said conduit; a worm disposed within said conduit for advancing the coating material therethrough, the outer diameter of the worm being smaller than said discharge end; and a readily releasable rigid connection in said conduit between said shaft and said worm, said worm being supported entirely by said connection, so that upon release thereof said worm may be removed through the discharge end of said conduit without the necessity of removing said shaft from said bearing.

6. Apparatus for applying plastic coating material, said apparatus comprising conduit means for carrying said material, a worm disposed within said conduit for advancing said material to the discharge end of said conduit, a pair of rotary bnushes adapted to receive said material from said worm, power means to drive said worm, a backing plate between said conduit and said brushes, said plate being substantially flat and having an opening therethrough to permit flow of material from said worm to said brushes, and a splitter plate positioned forwardly of said opening, said splitter plate being positioned substantially normal to the plane of said backing plate whereby the tendency of the material to spiral as it is being transferred to the worm from the brushes will be eliminated.

7. Apparatus according to claim 6, wherein said worm comprises three helical flights, each of said flights having one end thereof in a common radial plane and substantially equally angularly spaced, one of said flights extending substantially the full length of the worm, the other two flights being of shorter length than said one flight.

8. Apparatus according to claim 6, wherein said power means comprises a drive shaft extending rearwardly from said worm, and a flanged connection between said drive shaft and said worm.

9. Apparatus acconding to claim 8, wherein said conduit is provided with an opening therethrough, and removable cover means for said opening whereby the conduit wall may be sealed during coating operations and whereby access for cleaning purposes is provided upon removal of said cover means.

.10. A worm for use in a machine of the type employing a worm conveyor and rotary impeller brushes to apply plastic coatings on pipe, said worm comprising a shaft, and three helical worm flights on said shaft, one of said flights extending substantially the full length of the shaft, the other two flights extending for only a portion of the length of the shaft.

11. A worm for use in a machine of the type employing a worm conveyor and rotary impeller brushes to apply plastic coatings on pipe, said worm comprising a shaft, a helical Worm flight surrounding said shaft and extending for at least one convolution along said shaft, and an additional pair of helical worm flights surrounding said shaft and extending an amount less than one convolution along said shaft.

12. A worm for use in a machine of the type employing a worm conveyor and rotary impeller brushes to apply plastic coatings on pipe, said worm comprising a helical flight extending substantially the full length of the worm, and a pair of partial flights at the discharge end of the worm, all of said flights having their leading edges in substantially the same radial plane, said partial flights extending through a helical travel of approximately 180.

13. A worm for use in a machine for applying plastic coating materials, said worm comprising a central shaft, and three helical flights on said shaft, each of said flights having the leading edges thereof in substantially the same radial plane as the leading edges of the other flights, one of said flights having a constant pitch and extending for at least one full convolution along said shaft, the other two flights being angularly spaced from said one flight and from each other, said other two flights having the same pitch as said one flight, said other two flights extending in their helical paths approximately around said shaft.

14. A device for applying plastic coating material, said device comprising: a material carrying conduit; upper and lower rotatable brushes at the discharge end of said conduit for receiving material therefrom; a worm disposed within said conduit for advancing material therethrough toward said brushes, said worm comprising a shaft, a helical worm flight surrounding said shaft and extending for at least one convolution along said shaft, and an additional pair of helical worm flights surrounding said shaft and extending an amount less than one convolution along said shaft.

15. A device according to claim 14 and including a nozzle between said conduit and said brushes, said nozzle comprising spaced upper and lower plates converging toward said brushes, said plates being movable linearly to vary the size of the nozzle opening.

16. A device according to claim 15, wherein said spaced plates partially overlap the lower brush.

17. In apparatus for feeding plastic coating material to a device for applying said material to a workpiece; the combination of a conduit having a discharge end, readily removable means on said discharge end of the conduit to guide said material to said device, readily releasable means for locking said removable means on said conduit, said conduit having a closed end with an opening, a power drive worm shaft having a rotatable sealed mounting in said opening and extending into the conduit, a worm in said conduit for forcing said material therethrough to said discharge end thereof, readily releasable means in the conduit connecting the worm to the shaft for rotation therewith, said worm being supported entirely by said connecting means so that upon release of said rei leasable means and removal of 'said', deYicQ, the removable means may be nemoyed from said; conduit and the worm may be rem ved through the discharge endqof the cenduit' Without disturbing said" sealedj mounting.

References Cited inthefile of this patent UNITED STATES PATENTS 2,3695745; Millardet a1; Feb. 20, 1945 

